The ratio of P-wave to S-wave velocities, Vp/Vs, within the Earth depends on
Show Hint
- bulk modulus
- shear modulus
- density
- coefficient of internal friction
The Correct Option is A, B
Solution and Explanation
The P-wave (primary wave) and S-wave (secondary wave) are seismic waves that travel through the Earth. P-waves are compressional waves, and S-waves are shear waves. The velocities of these waves depend on the properties of the Earth's materials.
Step 2: Relationship Between P-wave and S-wave Velocities
The velocity of P-waves (Vp) and S-waves (Vs) is influenced by the material's bulk modulus, shear modulus, and density. However, the ratio of P-wave to S-wave velocities (Vp/Vs) primarily depends on both the bulk modulus and shear modulus of the material.
Step 3: Comparing the Options
Bulk modulus: This affects the velocity of P-waves. Since P-waves are compressional, the bulk modulus plays a significant role in determining their velocity.
Shear modulus: This affects the velocity of S-waves, which are shear waves. The shear modulus directly influences S-wave velocity and therefore impacts the Vp/Vs ratio.
Density: Affects both P-wave and S-wave velocities but does not influence the ratio as strongly as the moduli.
Coefficient of internal friction: This is not a key factor in determining the ratio of P-wave to S-wave velocities.
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